DEFINITY,Trivex, and Transitions...........

[hcjilson]

to get a thread going is address it to the right people! :D:D

[optigrrl]

"We found that the mean impact resistance of the Phoenix lenses was greater than the level required of eye protector lenses by the standards AS/NZS 1337:1992, ANSI Z87.1-2003 and CSA Z94.3-02. Similar to CR39 and polycarbonate, the application of MAR to Phoenix lenses reduces their impact resistance, however, they provide an acceptable level of impact protection in industrial settings, where there is little danger of exposure to pointed or sharp-edged high-speed missiles.

Submitted: 26 April 2005
Revised: 5 August 2005
Accepted for publication: 20 August 2005

Yay, Hoya!!!!

[HarryChiling]

Fezz, I did start a thread about this a few weeks ago but it didn't go anywhere.

Thanks for all the links and information, people! :cheers:

You'll also find that flatter base curves reduce impact resistance, so what's an optician to do skip the AR and thin lenses? No you move on even with AR on trivex it's still a more impact resistant lens than many lenses with AR or not.

[optiman37]

Usually a relationship with three ends in disaster, this is the one exception to that rule and has answered my prayers.

My love for DEFINITY lenses is no secret- It's been going on since I first tried the product. The wider field of vision, useable periphery, and ground view advantage have made this lens my progressive of choice for the past 4 or 5 years. My plea's for an edition in Trivex fell on deaf ears at J&J's Spectacle Lens Group. I think they had all they could do to keep up with the demand for the product in CR-39, Poly, and 1.60.

My love for Transitions and Trivex is not a well kept secret either. You can research this by plugging these terms into our search engine and following along the conversation. Please pay particular attention to the "Trivex" wars between Pete Hanlin vs Billy Brock and me. :D:D

In any event, Essilor is now the source for Definity and in my opinion, have carried the product to new heights, releasing a 1.67 version, and a Trivex DEFINITY this past winter. This was an absolutely superior product to the others because of the clarity and weight, but still lacked the one ingredient to make it complete.

A little over a week ago Essilor released the DEFINITY in Trivex Transition in grey or brown. I got mine just before lunch today and I am here to say that this lens is the best product I have ever seen......or seen through!..... That is in my career........and that started officially on August 26th 1959 so I've seen one or two come down the pike. This lens is AWESOME SQUARED! You may recommend this product with complete confidence that the wearer will still thank you for it....even after writing the check.
Give it a try!
Harry C Jilson

regarding the trivex lense. I work and have sold the trivex line bifocal and have to comments from customer that the optics is not as good as poly or plastic line bifocal. It was that bad that they changed out from trivex lenses

[Fezz]

regarding the trivex lense. I work and have sold the trivex line bifocal and have to comments from customer that the optics is not as good as poly or plastic line bifocal. It was that bad that they changed out from trivex lenses

That is just silly! Come on.....I think that there may be more to the patients complaints than Trivex. Swing over to the General optics Forum. I posted some info for you in another thread concerning this very issue!

[Craig]

That is just silly! Come on.....I think that there may be more to the patients complaints than Trivex. Swing over to the General optics Forum. I posted some info for you in another thread concerning this very issue!

This is what you are talking about.


Below is a post from Optiboard and the comparison is interesting! It shows
thickness is not an issue, but Trivex is clearly superior in the weight and
optics to poly and the other materials.
This information can be made into a very compelling marketing piece and help
further the cause of no more poly. Hope it helps get the marketing juices
flowing.

Thicknesses at 50mm, using -1.50 sph equiv.

CR-39 = 3.2mm
Trivex = 2.6mm
Poly = 2.5mm
1.67 = 2.3mm

1.67 is the thinnest by 0.2mm, let's look at the sacrifice

Chromatic Aberration threshold of 0.1

CR-39 = 33mm from OC = 100 percent of the lens area is below threshold
Trivex = 25mm from OC = 100 percent of the lens area is below threshold
Poly = 17mm from OC = 68 percent of the lens area is below the threshold
1.67 = 18mm from OC = 72 percent of the lens area is below threshold

Weight:

CR-39 = 6.7g
Trivex = 4.5g
Poly = 4.7g
1.67 = 5.2g

Trivex seems to be the best choice to me in this scenario, lighter in
weight, provides crisp optics throughout a generous portion of the lens, and
only slightly thicker, however if we were to surface trivex down to 1.0mm CT
then it would be thinner as well so it's obviously the better choice here.
Craig

[Robert Martellaro]

In any event, Essilor is now the source for Definity and in my opinion, have carried the product to new heights, releasing a 1.67 version, and a Trivex DEFINITY this past winter. Harry C Jilson

Glad you like the product, Harry. I still prefer polycarbonate as a substrate- and my blood still runs Varilux blue- but the fact that professionals such as yourself (and many others who have communicated with me over the years) find the performance of DEFINITY to be exceptional is not lost on me. Pete

I tried the JJ lens when it came out about five years ago. I have them in front of me- the fitting cross is 1mm above the 180 (they're poly). Back then, the lens was not atoric, used a standard inset, and had no off-axis optimizations. A portion of the Add was placed on the back using free-form generators.

Question.

Is this lens (the JJ Definity) the same lens design as the Essilor Definity? If not, what is different?

[Samuel Jong]

Should we use two steps fining for Trivex lens?

[Fezz]

Should we use two steps fining for Trivex lens?

Sam,

Here is everything you wanted, need, and could care less about Trivex lenses!

Try here:

http://www.youngeroptics.com/trilogy.aspx

They have a whole section on processing Trivex!

This is also a good site!


http://corporateportal.ppg.com/NA/ch...ptical/Trivex/

Good luck!

:cheers::cheers::cheers::cheers:

[Samuel Jong]

Sam,

Here is everything you wanted, need, and could care less about Trivex lenses!

Try here:

http://www.youngeroptics.com/trilogy.aspx

They have a whole section on processing Trivex!

This is also a good site!


http://corporateportal.ppg.com/NA/ch...ptical/Trivex/

Good luck!

:cheers::cheers::cheers::cheers:

Fezz, thanks a lot. :cheers:

[KStraker]

I've asked this a couple of times now(in other threads) and no one has answered. So, I'd still like to know how the ground view advantage effects the size of the reading area in the Definity short? Do they take this zone in to account when they list the minimum seg ht? Thanks-kevin

[rinselberg]

I've asked this a couple of times now(in other threads) and no one has answered. So, I'd still like to know how the ground view advantage effects the size of the reading area in the Definity short? Do they take this zone in to account when they list the minimum seg ht? Thanks-kevin

You could send your question via email to the Definity group at Essilor:

http://www.Definity.com/Professional...Contact+Us.asp

[KStraker]

You could send your question via email to the Definity group at Essilor:

http://www.Definity.com/Professional...Contact+Us.asp

There is an Essilor rep in this thread and others who swear by this lens. Yet, three days later, still no response. Something is starting to smell funny.

[hcjilson]

Can you possibly think there is a sinister plot afoot because of your question?

Kevin,
I do not now, nor have I ever worn the DEFINITY short so I am at a loss to give you an answer from a wearers standpoint but I think your question more properly should be, does the reading area affect the ground view advantage, rather than the other way round. You must remember that the reading area is the reason for the lens to begin with, and the ground view advantage was a spin off of the lens design. It was never the reason J&J designed the lens. I have only sold a few shorts and have had no complaints. I am not avoiding your question but I am not answering it either.

I would think if the answer were that important to you that you would have followed Rinsie's advice and gotten it straight from the horses mouth..as it were./
hcj

[KStraker]

Can you possibly think there is a sinister plot afoot because of your question?

Kevin,
I do not now, nor have I ever worn the DEFINITY short so I am at a loss to give you an answer from a wearers standpoint but I think your question more properly should be, does the reading area affect the ground view advantage, rather than the other way round. You must remember that the reading area is the reason for the lens to begin with, and the ground view advantage was a spin off of the lens design. It was never the reason J&J designed the lens. I have only sold a few shorts and have had no complaints. I am not avoiding your question but I am not answering it either.

I would think if the answer were that important to you that you would have followed Rinsie's advice and gotten it straight from the horses mouth..as it were./
hcj

OK, maybe the smell was the Bojangles biscuit I had for breakfast. I wanted the more objective opinions of practioners and wearers. Maybe I'll have to ask the manufacturer, but I trust your opinions more. What the heck ,I'll ask Essilor and see what they have to say.

thanks-kevin


HJC-Looking at the lens diagram, I see your point regarding the phrasing of my question. I guess a better question would be, if you set the bifocal ht at 15mm how far down from the fitting cross does the GVA start?

[Happylady]

I've asked this a couple of times now(in other threads) and no one has answered. So, I'd still like to know how the ground view advantage effects the size of the reading area in the Definity short? Do they take this zone in to account when they list the minimum seg ht? Thanks-kevin

My newest glasses are Definity Short. I think I have them at 18, but I'm not sure. I notice no groundview advantage. The reading area goes all the way to the bottom.

I do think the reading area at 18 is not very deep. It's wide enough, but deeper would be better. The intermediate is good as is the distance.

[KStraker]

My newest glasses are Definity Short. I think I have them at 18, but I'm not sure. I notice no groundview advantage. The reading area goes all the way to the bottom.

I do think the reading area at 18 is not very deep. It's wide enough, but deeper would be better. The intermediate is good as is the distance.

Thanks for the opinion. I guess with free form generators you can put the bifocal wherever you want it, with respect to the GVA area. This is speculation since the people at Essilor have not answered my email.

[hcjilson]

why not just email Pete Hanlin directly. If he can't answer your question, he can hook you up with someone who can.I imagine they get one or two inquiries a day and perhaps are running behind.